The Allium family of vegetables includes onions, garlic, leeks, chives, shallots, and scallions. Epidemiological studies have found that increased consumption of Allium vegetables is associated with decreased risk of several cancers. For example, one large European study found striking risk reductions in the participants who consumed the greatest quantities of onions or garlic for oral, esophageal, colorectal, laryngeal, breast, ovarian, and prostate cancers. A fifty-five to eighty percent reduction of almost all major cancers. Amazing!
Anti-Cancer Effects of Onions and Garlic
Allium vegetables are rich in cancer-fighting organosulfur compounds, which are produced when the cell walls of the vegetables are broken down by chopping, crushing, or chewing. These compounds are thought to be mostly responsible for the cancer-protective effects of Allium vegetables. In scientific studies, organosulfur compounds prevent the development of cancers by detoxifying carcinogens and halting cancer cell growth. These garlic and onion phytochemicals are also anti-angiogenic, which means that they can prevent tumors from obtaining a blood supply to fuel their growth. In studies of breast cancer cells, garlic and onion phytochemicals have caused cell death or halted cell division, preventing the cancer cells from multiplying.
Onions, garlic, and their family members also contain flavonoids and phenols. White onions are not as rich in these antioxidant compounds as yellow and red, and shallots are especially high in polyphenol levels. Red onions are particularly rich in anthocyanins (also abundant in berries) and quercetin. Flavonoids such as quercetin can contribute to preventing damaged cells from advancing to cancer, and also have anti-inflammatory effects that may contribute to cancer prevention.
Onions and the other vegetables of the Allium family can be added to any and every vegetable dish for great flavor and anti-cancer benefits. Remember that they must be eaten raw and chewed well or chopped finely before cooking to initiate the chemical reaction that forms the protective sulfur compounds. When you cut onions and your eyes begin to tear, they are creating the anti-cancer sulfur compounds.
How to Cut an Onion to Maximize Anti-Cancer Compounds and Minimize Eye Irritation:
- Make sure that the onion is cold before you cut it. Even putting the onion in the freezer for 5 minutes is sufficient.
- You can use a fan to blow the gaseous compounds away from you if you like.
- Cut the end of the root off with the root facing away from you, preserving as much of the onion adjacent to the root as possible. The root is the part of the onion with the highest concentration of these anti-cancer compounds.
- Make sure to then cut or chop the onion finely, slice thinly, or put it in a food processor before adding to your soup, salad, or vegetable dish to maximize the production of sulfur compounds.
I discuss the anti-cancer effects of onions, garlic and their family members in detail in my most recent book, Super Immunity.